30) A scientific theory is based on
A)
data collected over time.
B)
a general claim by scientist.
0
the best guess of a scientist.
D)
an idea that can only be proven true.

I think it’s (a)but, I’m not sure.

D has to be based on facts so d would be the answer and idea that can only be proven true those are facts not hypothesis or guesses

Explanation:

based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world."

why do the isotopes of a particular element behave differently in nuclear reactions but the same in chemical reactions? chemical reactions involve changes to electrons in an atom; isotopes do not differ in electrons, and so they react the same way during chemical changes.

since electrons are negative the answer is neagtaive