Enjoy oneself in a lively and noisy way, especially with drinking and dancing.

lively and noisy enjoyment, especially with drinking and dancing.

Correct Option: C

Verb
1.
enjoy oneself in a lively and noisy way, especially with drinking and dancing.
"they spent the evening reveling with their guests"
synonyms : celebrate, make merry, have a party, party, feast, eat, drink, and be merry, carouse, roister, have fun, have a good time, enjoy oneself,
"with their exams out of the way they revealed all night"
Noun
1.
lively and noisy enjoyment, especially with drinking and dancing.
"late-night revels"
synonyms: celebration, festivity, jollification, merrymaking, carousal, carouse, spree, debauch, bacchanal; party, jamboree; informal rave,
"there are a few spots in town for night revels"

A difficult or unpleasant situation.

Correct Option: B

Noun
a difficult or unpleasant situation.
"resilience in the face of adversity"
synonyms : misfortune, ill luck, bad luck, trouble, difficulty, hardship, distress, disaster, misadventure, suffering, affliction, sorrow, misery, heartbreak, heartache, wretchedness, tribulation, woe, pain, trauma, torment, torture; mishap, stroke of ill luck, stroke of bad luck, accident, shock, upset, reverse, reversal, reversal of fortune, setback, crisis, catastrophe, tragedy, calamity, trial, cross, burden, blow, buffet, vicissitude, issue; hard times, dire straits, trials and tribulations; informal hell, hell on earth, hassle, stress; travails
"they remain steadfast in the face of adversity"

savagely violent.

Correct Option: D

savagely violent. "a brutal murder"
synonyms : savage, cruel, bloodthirsty, vicious, ferocious, barbaric, barbarous, wicked, murderous, cold-blooded, hard-hearted, harsh;

walk in a leisurely way.

Correct Option: A

Verb
1.
walk in a leisurely way.
"I strolled around the city"
synonyms : saunter, amble, wander, meander, ramble, dawdle, promenade, walk, go for a walk, take a walk, roam, traipse, stretch one's legs, get some exercise, get some air, take the air; More
2.
achieve a sporting victory without effort.
"the horse strolled home by 12 lengths"
Noun
1.
a short leisurely walk.
"we took a stroll in the garden"
synonyms: saunter, amble, wander, walk, turn, promenade, airing, breather; More
2.
a victory or objective that is easily achieved.

Decline means reduce , Discomfiture means awkwardness and Degeneration is also decline .

Correct Option: B

The word Debacle (Noun) means: an event or a situation that is a suden or complete failure. Hence, the words debacle and downfall are synonymous.