Answer:
The answer is "A"
Explanation:
They cannot make their own food, they are heterotrophs
It is true that situational context is the social and environmental setting in which a particular behavior takes place.
Answer:
B)attach specifically to host cell receptors
Explanation:
Viral spikes are one of the envelope proteins. These proteins are coded for by viral genes. Viral spikes project from the envelope surface. They are also called peplomers. One of the functions of these spikes is to specifically interact with the receptors present on the surface of the host cell to mediate the attachment of the virus to the host cell surface. Viral spikes and the host cell surface receptors are complementary to allow their specific binding. For example, the spike protein of the SARS-coronavirus bind specifically to the human host cell receptor ACE2.
