Who was the life of the party at the 12th annual Meridian House ball last night?

a. Russian Ambassador Anatoliy Dobrynin, who danced like a debutante to "Anything Goes"

b. Former transportation secretary Brock Adams, who was fired by Jimmy Carter and wouldn't say whom he'll vote for.

c. Mayor Marion Barry, who's backing Carter and said if Reagan wins there'll be "tensions between blacks and whites and Jews and rural and urban people"

d. The saxophone player

Answer: a. Anatoliy Dobrynin. Hands-down winner, especially since he hasn't been on the scene lately, what with his vacation and Afghanistan. Good dancer, too. Brock Adams was charming, but doesn't have the foreign cachet. Barry's too local. And nobody knew the sax player. Party Poll

Who gave the most talked-about embassy dinner party before this ball that benefits Meridian House International, a cultural exchange program?

a. The French

b. The Russians

c. Protocol chief Abelardo Valdez and his wife, Margarita, at Blair House

Answer: b. The Russians. A close one, but Dobrynin wins again because he had caviar. And seconds on caviar. "It was from Russia," he pointed out, "not Iran."

Still, the French came close. "The main course was lamb, and the first course, my dear, was cheese souffle," said Jayne Ikard, wife of mogul Frank. "The dessert was a cold Egyptian souffle. And the wine! A '75 claret! And champagne!" Talk of Tasties

A meaningful party conversation that occurred between Carol, Anne and Margaret on the outside terrace under linden trees:

Carol: "What did you have for dessert?"

Anne: "Sort of a chocolate torte with almonds, and you know, everybody had seconds. I couldn't believe it."

Carol: "We had a vanilla ice cream cake with meringue and raspberries."

Margaret: "We went to Blair House."

Carol: "That was better yet. What did you have for dessert?"

Margaret: "I didn't eat any."

Carol and Anne, in unison: "Oh, Margaret." The Decor

The scenery inside glorious Meridian House, built in 1922 as the fulfilled daydream of American millioniare Irwin Laughlin:

a. Dahlias the size of soccer balls

b. Marble floors, grand columns, a greenish satyr with human feet instead of goat hooves

c. Fruit decorations that included real, not plastic, grapes and also those funny green mock oranges that kids roll out in the streets so they can watch cars smash over them

d. Strawberry cheesecake, macaroons and chocolate-covered bananas Pearls From the Pundits

Two presidential election assessments made during the ball, underwritten this year by Allegheny Ludlum Industries Inc.:

a. "I think there are a great many voters who haven't decided what to do. The thing is out there to be won. But the advantage of losing, of course, is that there's a chance to catch up on my sleep." This was from Rick Neustadt, an assistant to presidential domestic policy adviser Stu. Eizenstat.

b. "The election is gonna be a squeaker." This was from Mayor Barry, who's backing Carter. Costume Contest

Who had on the most absorbing evening attire at the ball, one of the remaining Washington social functions where many of the hundreds of guests get carried away with sequins, feathers, rubies, etc.?

a. A woman in a long orange boa

b. A woman who carried, not wore, a leopard-skin coat

c. Sheila Routh, wife of painter and writer Jonathan Routh, in an Indian dress bought in London

d. Aniko Gaal, public relations director of Garfinckel's, in a Mary O'Donnell

Answer: d. Gaal, in the Mary O'Donnell. It was silk, the color of yellow maple leaves, had pleated sleeves that puffed out like balloons, 20 buttons (about half of them open) down the front, and cost $1,200. "You can't imagine," said its wearer, "I feel like a million dollars inside."

Routh, in the Indian dress, was interesting but unexotic. Boas and leopards you can find in countless places. Select Scenes

Three odd party scenes:

a. A large knot of waiting chauffeurs, collected on the corner of Belmont and 16th Street for what they called "The Chauffeur's Ball." This amounted to sandwiches and soda from the back of a truck, courtesy of Ridgewell's Caterers. (Ridgewell's also flew a mini-dirigible emblazoned with "Ridgewell's" from their passion-purple truck.)

"No booze," sighed Gregg Wilson, who was driving a congressman around.

b. Two magazine photographers who were situated in a corner to take pictures of party fashions. They had a big umbrella to absorb the flash.

"This is the Ringling Brothers Barnum and Bailey Circus," said the photographer, Mike Mitchell. "We're about to set up a trapeze."

c. A young couple who drank champagne on the outside balcony as the lights from a gurgling fountain made them look like characters from a Fitzgerald short story. Were they married, or in love?

"Neither," said the woman. "I hardly know him."

"We'll settle that later," said the man.