Scientific

a. can be changed and revised

b. need to be proven only once

c. are not subject to revision

d. become laws when they are proven

answer'(basidium)the spore--bearing structure of a basidiomycete is called a basidiocarp; ///

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.

the answer is d. none of the above