_________ मिश्र धातूचे, उच्च सामर्थ्य ते वजन गुणोत्तर प्रामुख्याने विमान आणि ऑटोमोबाईल उद्योगांमध्ये वापर करण्याची शिफारस करतात.

Choose option D: Light aluminium alloys deliver high strength-to-weight ratios prized in aircraft fuselages and automobile bodies—mass reduction without sacrificing structural integrity. Light steel, copper, or titanium options misidentify the metal the transport industry most commonly lightweights at scale. Distractors A (light steel), B (light titanium), C (light copper) look plausible but do not follow from the facts stated in the question. Keep the name, formula, and unit together in your notes — that helps you spot incomplete distractors quickly.