How do rhizoids fungi to obtain food?
they produce enzymes which break down organic molecules into a useable form.
they produce deep roots in order to draw more nutrients from the soil.
they change the molecular structure of the cell wall so nutrients can easily be absorbed.

without spores, fungi could not:
obtain food
conduct respiration
reproduce
differentiate cells

fungi are grouped into club fungi or sac fungi according to:
the shape of their spore-producing structures
the number of hyphae they possess
the shape of their cap
their reproduction method

Q1. The answer is They produce enzymes which break down organic molecules into a useable form.

Rhizoids are hair-like structures similar to roots of vascular plants. But roots are multicellular and rhizoids are unicellular structures. The functions of rhizoids are the absorption of water and minerals from the soil and a support of the fungi. Fungi are heterotrophs, which means they do not produce organic compounds. On the contrary, in rhizoids, they produce enzymes break down organic molecules into a useable form which fungi can absorb.

Q2. The answer is reproduce.

Spores of the fungi can be part of asexual or sexual reproduction. In either case, spores are actively dispersed from their reproductive structures. This ensures travelling of spores through the air. Once the conditions are fulfilled, spores can develop into a number of different phases of the complex life cycles of the fungi.

Q3. The answer is the shape of their spore-producing structures.

The shape of the spore-producing structures (asci and basidium) determines the group of the fungi. Spores of sac fungi are produced in sacs called asci. Those sacs are coloured and shaped as balls. Spores of club fungi are produced in structures called basidium which is club-shaped structure.