The fourth one that looks like an M. This is because it describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups.
Answer:
The commercial application of ethylene gas are as follows:
The ethylene gas are important for the early ripening of fruits.
The elongation of shoot can be done by ethylene gas.
The flower stimulation and swelling of stem can be achieved by the use of ethylene gas.
The leaf abscission of ornamental plants can be done by the use of ethylene hormone.
Your answer is leukocytes.