Intercalary veins and numerous cross veins present in case of

Answer: Option D

Intercalary veins and numerous cross veins are present in the case of Ephemeroptera.
Ephemeroptera is the Soft-bodied insect with short setaceous antennae and vestigial mouthparts derived from a biting type.
Wings membranous, held vertically upwards when at rest, the hind pair considerably reduced; ‘intercalary’ veins and numerous cross-veins usually present.
Cross-veins are transverse veins joining longitudinal veins. The costal cross-veins here are not homologs of those found in Odonata (or Ephemeroptera) which are flattened and triangular.