In the question below, a sentence is given, divided into parts which when rearranged will form a logical and coherent sentence. One of the parts does not belong to the sentence. Identify the part that does not belong to the sentence and rearrange the remaining parts to form a meaningful sentence. Choose the option that represents the correct arrangement and mark the options accordingly. 1. relying on highly sensitive infrared imaging instruments 2. and observe the rapid formation of the universe's earliest galaxies 3. the launch vehicle experienced minor delays due to adverse weather 4. to peer directly through dense clouds of cosmic dust 5. the modern orbital observatory is specifically engineered

(a) is the right answer as 5142 is the correct sequence and part 3 is the odd part. Part 5 introduces the main subject—the modern orbital observatory is specifically engineered. Part 1 explains the method or tool it uses—relying on highly sensitive infrared imaging instruments. Part 4 explains the primary function of these instruments—to peer directly through dense clouds of cosmic dust. Part 2 concludes by stating the ultimate goal of peering through the dust—and observe the rapid formation of the universe's earliest galaxies. Part 3 is the odd part out as it discusses logistical delays regarding a launch vehicle, which is entirely irrelevant to the sentence explaining the scientific capabilities and engineering purpose of the observatory.