سوال ۱ کنکور ارشد علوم کامپیوتر ۱۴۰۱

The sentence pairs the blank with "and necessary", signalling a word that means certain to happen / unavoidable.

• inevitable — impossible to avoid or prevent; sure to happen. This fits perfectly: aging and growing decrepit are an inevitable and necessary part of being human.
• intangible — not able to be touched or grasped; vague. Wrong meaning here.
• unforeseeable — impossible to predict. But aging is entirely predictable, so this contradicts the sentence.
• unsentimental — not influenced by emotion. Irrelevant to the idea of an unavoidable life process.

The natural collocation "an inevitable and necessary part of..." confirms option 1.

Exam trick: When a blank is joined by and to another adjective (here "necessary"), pick the option whose meaning runs parallel to that adjective. "Necessary" → something that must be → "inevitable."