Option A is the only option where both muscles are part of the orbital floor. Also, the last sentence in the question stem is a total modifyer of what one would expect the question to be asking. It is not asking for you to assume that these muscles have been severed, paralyzed, or rendered flacid. It is asking you to assume that they have become "entrapped" if the muscle is entrapped, then it cannot allow the eye to move into whatever position it would be in when the muscle is at its lengthened position. So in this case, It is the inferior rectus being entrapped in a functionally shortened position that is preventing upward gaze.
I thought regarding this question as HLA gene distribution (en block).
Even if we discard everything and just think about the last sentence (question), for any gene, chance of sibling having exact same allele is 25%
suppose there are 4 alleles for a gene in parents, A,a, B, and b (what I mean to say is all 4 are different in both parents).
Now suppose one daughter has aB genotype. To have exact same alleles, other daughter must have
50% chance of a (among a and A from mother) multiplied by 50% chance of B (among b and B from father)
combined probability for any gene would be 25%.
Please, point out any fault in the reasoning.