C because the arrows are pointing away from them (brainless??)
The answer is amino acid
the basic building block of a protein is called an amino acid. There are 20 amino acids in the proteins you eat and in the proteins within your body, and they link together to form large protein molecules.
The correct answer should be because they want to establish a sense of time passing by and things changing over the course of time. Each new era is influenced by the previous one so the way time passes is important because as time passes by things change and the historians monitor it and record it in a chronological order.
Answer:
Because the have similar limbs.
Because they have similar functions.
Explanation:
(because they have similar limbs)
Homology (evolution) describes a structure that has similar function like limbs on dogs and bears (used for walking) and also have a similar arrangement of bones. The fins on a doplhin might be different from the wings on a bat but they reflect a common origin due to their bone composition e.g carpals and radius bones.
(because they have similar functions)
Analogy (evolution) describes a structure with for example, bird and butterfly wings that have no common ancestor but have the same purpose, in this case flying. They developed independtly as adaptions. This supports natural selection which is a driving force for evolution.
It's very likely that the catcus with short spines will die out faster than the cactus with long spines.
