EXPLAIN Cell theory changed over time as new discoveries came to light. What does this say about a scientific theory? Select all correct answers.
a. A theory is based on ideas that have been proven true and that are not subject
to revision.
b. A theory is a proposed explanation for a wide variety of observations and
experimental results.
c. New evidence that has been confirmed through observation and experiment
may result in the modification of a theory.
d. A theory is based on preliminary evidence but still needs to be confirmed
with experiments.