Answer:
Subjects and verbs must AGREE with one another in number (singular or plural). Thus, if a subject is singular, its verb must also be singular; if a subject is plural, its verb must also be plural. verbs REMOVE an s from the singular form.
Answer:
It is B. Proteins
Explanation:
Tumor markers are substances, often proteins, that are produced by the cancer tissue itself or sometimes by the body in response to cancer growth.
