Desert and desert-scrub biomes are characterized by specific types of plant and animal life. creosote bushes are found throughout areas such as the mojave desert. they are used by roadrunners for nesting, and also provide a home for desert tortoises.
a. coniferous tree
b. lichen
c. shrub
d. flowering weed

Creosote bushes shrub are found throughout areas such as the Mojave Desert.

c. shrub

Explanation:

The Creosote bushes is an evergreen shrub. It is commonly grows at elevation under 5000 feet in lower Chihuahuan, Sonoran and Mojave deserts of North Mexico and United States. The bushes are named as Larrea Tridentate.

This shrub is act as roadrunners for nesting and place for desert tortoise. The structure of the shrub is coated with tiny pointed green leaves. These leaves are adopted to conserve water and survive high temperatures.

The creosote bush completes with other plants for water in the soil, and grows in desert condition. The tortoise present in the desert builds the subterranean burrows and spends 95% in the bushes. The bushes protect the tortoise from the intense heat in summer.

it's c. (to reduce the greenhouse effect/carbon gasses)