Which of the following provides evidence that cell signaling evolved in the early history of life? (a) comparative studies of mitochondrial dna(b) studying fossils found in different regions of the earth(c) studying fossils found in different regions of the earth(d) comparisons of mechanisms in organisms with distant common ancestors

Option (D).

Explanation:

Cell signalling may be defined as the process of communication that helps in the cell activities and their coordination. Cell signalling activities are important for tissue repair, homeostasis and immunity.

The evolutionary evidence are also available that cell signalling was present in early life. The comparison of the ways of cell signalling mechanism in the organism with distant common ancestor had explained the evolutionary cell signalling. The mechanism are quite similar in today's organism and in their ancestor.

Thus, the correct answer is option (D).