The correct option is D I - Q, II - R, III - S, IV - P
Prior to Mendel’s theory and even after that, various scientists had put forward their own theories regarding heredity in organisms. Some of them were accepted widely for a long period of time too. The theory of pangenesis was proposed by Charles Darwin, in which he proposed that each part of the body continually emitted its own type of small organic particles called gemmules that aggregated in the gonads, contributing heritable information to the gametes.
The preformation theory states that organisms develop from miniature versions of themselves. Instead of assembly from parts, preformationists believed that the form of living things exists, in real terms, prior to their development. One of the earliest proponents of this theory was Jan Swammerdam.
August Weismann proposed the continuity of germplasm theory, which states that multicellular organisms consist of germ cells that contain and transmit heritable information, and somatic cells which carry out ordinary bodily functions. Genetic information cannot pass from somatoplasm to germplasm and on to the next generation.
The moist vapor theory of inheritance was an ancient theory proposed by the Greek philosopher Pythagoras, who proposed that each organ of the male body produced moist vapours during coitus which formed the body parts of the embryo.