What is the shape of the DNA molecule as determined by Franklin, Watson & Crick?

Ectocarpene is a volatile, sperm cell-attracting material released by the eggs of the seaweed ectocarpus siliculosus. its constitution is all the double bonds are cis, and the absolute configuration of the chirality center is s. draw a stereochemically accurate representation of ectocarpene.

Ineed to know why d is the correct answer asap

Modern whales developed their traits through natural selection what occurs during the process of natural selection