Answer:
A. dihybrid crosses
Explanation:
A dihybrid cross can be defined as a mating experiment between two lines/varieties/organisms that differ in two phenotypic traits. By using pea plants, Mendel performed dihybrid crosses in order to analyze the mode of inheritance of both phenotypic traits at the same time. From these mating experiments, Mendel observed that the inheritance factors (nowadays called genes) sorted independently from one another in the next generation, which is called the principle/law of Independent Assortment.
The same day an event occurs or a vulnerability is discovered.
In 1884, a bacteriologist named Christian Gram created a test that could determine if a bacterium had a thick, mesh-like membrane called peptidoglycan. Bacteria with thick peptidoglycan are called gram positive. If the peptidoglycan layer is thin, it's classified as gram negative.
B.cyanobacteria
hope it is correct