The correct option is C be distracted by other, mysterious sources of light
Option D is the correct answer. The glowworms give them direction and helps them find their way, but in their absence, every source of light appears the same to them, causing them to wander and get lost, get distracted. They all want to reach home, true, but it is the glowworms that lead them there. They're lost without them. Option E, suggesting them never being able to find their homes is the result to them being led astray by distractions in the absence of the glowworms, is thus, wrong. The statements of options A,B and C do not convey the tone of the poem, and are incorrect.