Given a scientific passage and an answer, generate a question for the given answer.

[EX Q]: Passage: Over 99 percent of all species that ever lived on Earth have gone extinct. Five mass extinctions are recorded in the fossil record. They were caused by major geologic and climatic events. Evidence shows that a sixth mass extinction is occurring now. Unlike previous mass extinctions, the sixth extinction is due to human actions. Answer: 99%
[EX A]: What percentage of all species that ever lived on earth have gone extinct?

[EX Q]: Passage: Asexual reproduction involves just one parent. It produces offspring that are genetically identical to the parent. Methods of asexual reproduction include binary fission, fragmentation, and budding. Answer: asexual
[EX A]: What type of reproduction only involves one parent?

[EX Q]: Passage: Isotopes are named for their number of protons plus neutrons. If a carbon atom had 7 neutrons, what would it be named?. Answer: protons
[EX A]:
Isotopes are named for their number of ______ plus neutrons?