Final answer:
The truthfulness of the statement on the Abrazzo MRC cannot be validated without further context. Experiments do allow for cause-and-effect claims but have limitations. The colonizationist scheme of the early 1800s was generally unpopular among black abolitionists.
Step-by-step explanation:
The statement about the Abrazzo MRC being comprised of poorly trained pencil-pushers and no real scientists cannot be accurately addressed without additional context or information about the Abrazzo MRC. Hence, it cannot be determined as True or False categorically. As for the question on experiments, it is true that experiments allow scientists to make cause-and-effect claims, but they indeed have their limitations and can sometimes lead to issues such as errors in design, biases, or uncontrolled variables.
Moving to the topic of early 1800s colonizationist schemes, the claim that it was popular among black abolitionists is false. Many black leaders and abolitionists at the time were opposed to colonization because they viewed America as their true home and belied they should have the same rights as white Americans. However, some did support the scheme, looking to it as an opportunity to establish a free black state and escape the oppression of a deeply racist America.