Who proposed Adventitious embryony?

Answer: Option C

Strasburger proposed Adventitious embryony.
In adventitious embryony also known as sporophytic apomixis, an embryo is formed directly (not from a gametophyte) from nucellus or integument tissue.
There may be a megagametophyte in the ovule, but the embryos do not arise from the cells of the gametophyte; they arise from cells of the nucellus or the integument. Adventive embryony is important in several species of Citrus, including Garcinia, Euphorbia dulcis, Mangifera indica, etc.