Alteration of generations is when plants alternate between two forms called
a. gametophyte and haploid
b. sporophyte and diploid
c. gametophyte and sporophyte
d. meiosis and fertilization

The correct answer is option c, that is, gametophyte and sporophyte.

Explanation:

In biology, the metagenesis or heterogenesis is also known as the alternation of generations. It refers to the alternation of an asexual phase and a sexual phase in the life cycle of an organism. The phenomenon of alternation of generation is found commonly in fungi, algae, and plants. In the process, the sexual phase known as the gametophyte generation generates sex cells or gametes, and the sporophyte generation or the asexual phase generates spores asexually.

the trilobite is used as an index fossil for various geologic time periods as specific types of the trilobites were present in different geological time periods. they are a group of marine arthropods belonging to the class of trilobita.

explanation:

the answer to your question is a plant