| Date | May 2009 | Marks available | 1 | Reference code | 09M.1.SL.TZ2.21 |
| Level | Standard level | Paper | Paper 1 | Time zone | Time zone 2 |
| Command term | Question number | 21 | Adapted from | N/A |
Question
Which process tends to reduce variety within a population?
A. Natural selection
B. Random fertilization
C. Independent assortment
D. Crossing over
Markscheme
A
Examiners report
Candidates should know that natural selection reduces variety within a population.
Syllabus sections
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