Researchers only need participants' informed consent when the researchers believe that harm may come to the participants during the study

Cassandra knows from her hours and hours of memorizing her times tables that 7 x 3 = 21 so that when her teacher asks her, she can easily bring the answer to mind. Cassandra is using which mathematical strategy?

A) decomposition B) fact retrieval C) regrouping D) counting manipulatives

__________ originate in the bone marrow, mature in the thymus, and attack foreign substances directly

A) T cells B) B cells C) Telomeres D) Antigens