In both mitosis and meiosis, must occur for the process to continue to completion.
A) crossing over
B) reduction division
C) chromosome replication
D) Homologous chromosomes form tetrads

C, chromosome replication

Explanation:

A, B, and D only occur in meiosis, as crossing over is required for genetic variation, which isn't needed in mitosis, reduction division is when diploids are reduced to haploids, which only happens in meiosis, and homologous chromosomes making tetras doesn't occur in mitosis either. However, during interphase of both mitosis and meiosis, chromosomes (DNA more specifically) are replicated.

d bonding propertys

explanation:

carbon can form so many different compounds not just with oxygen