Question

in order for a scientific investigation to be considered valid, the evidence produced by the investigation must be
a in the form of a graph.
b a way to prove the hypothesis
c replicable by others.
d conducted in a lab.

Explanation:

In scientific investigations, for evidence to be valid, it must be replicable by others. This ensures that the results are not due to chance or specific idiosyncrasies of the original experimenter. A graph (A) is just a way of presenting data, not a requirement for validity. Experiments don't have to be conducted in a lab (D) (field experiments are also valid). Also, in science, we don't "prove" hypotheses (B) in the absolute sense; we support or refute them based on evidence. Replication (C) is a key aspect of the scientific method to establish the reliability and validity of evidence.

Answer:

C. replicable by others