- A Sister chromatids pairing along their length
- B Homologous chromosomes pair up (synapsis)
- C Non-homologous chromosomes pairing randomly
- D All chromosomes aligning at the spindle equator
Correct answer: B. Homologous chromosomes pair up (synapsis)
Explanation: Bivalent (tetrad): two homologous chromosomes pair up (synapsis) in Prophase I. Each homolog consists of two sister chromatids.
Concept context
Mitosis and meiosis: how cells divide for growth, repair, and reproduction.