The correct option is D A- (ii), B- (iv), C- (i), D- (iii)
The ommatidia are the unit of compound eyes containing a cluster of photoreceptor cells surrounded by support cells and pigment cells in some insects.
The trochanter is the part of the femur connecting to the hip bone.
Coxa is the leg segment of the arthropod leg which articulates with the pleuron and associated sclerites of its thoracic segment.
Sclerites are the chitinous or calcareous plate of invertebrate, (one of the hard outer plates) forming the exoskeleton of the arthropod.
Therefore, the correct answer is option A.