If something is "antiquated," it is old-fashioned or out of date.

The 200 year old house’s antiquated heating system still used coal as its fuel source.

So "outdated" is the best answer.

"Abundant" means a lot; Diminutive means small; Famished means starving or without food; Dehydrated means without water or thirsty; and Implacable means cannot be be satsifed.

"Execrable" means detestable or very bad.

"Crude" means made in a rudimentary or makeshift way.

“Abundant” means plentiful, or well-supplied. For clarification, serendipitous means fortunate or relating to good fortune; vain can either mean pointless when used to describe an activity or action or it can mean obsessed with one’s own image if used to describe a person; poignant means moving, or particularly penetrating and perceptive.

The adjective "abominable" means horrible, gruesome, detestable and "loathsome." Additionally, "wizened" means weakened and wrinkled with age; "quixotic" means unrealistic, extremely impractical, based on romantic notions; "venerable" means deeply respected due to age and experience.

"Tantamount" means equal to.

“Insipid” is used to describe something unexciting. For clarification, "intrepid" means adventurous; "mournful" means full of sadness after a loss; "derisive" means disdainful or contemptuous.

"Tantamount" is an adjective that means "equal in seriousness to; virtually the same as," so we need to pick out another word that means "equal." While "indifferent" may look like a good answer choice because it looks like "in-" ("not") and "different," "indifferent" actually doesn't mean "not different," but instead means "having no particular interest or sympathy; unconcerned," or "neither good nor bad; mediocre," so it's not the word we're looking for. "Equivalent," however, means "equal in value, amount, function, or meaning," and because it is the answer choice closest in meaning to "tantamount," it is the correct answer.

"Ecumenical" and "catholic" both mean all-encompassing, universal. (Don't confuse catholic with "Catholic," a specific religious denomination.) "Germane" is an antonym for "irrelevant." "Exuberant" means overjoyed, while "tyrannical" means authoritarian and cruel.