The primary ${\mathrm{CO}}_2$ acceptor in ${\mathrm{C}}_4$ plants is:
1. RuBP in mesophyll cells
2. RuBP in bundle sheath cells
3. PEP in mesophyll cells
4. PEP in bundle sheath cells

In ${\mathrm{C}}_4$ pathway, the 4-carbon compound transported to bundle sheath cells most commonly is:

Identify the incorrectly matched pair:

Identify the incorrect statement regarding the comparison of ${\mathrm{C}}_4$ plants to the ${\mathrm{C}}_3$ plants:
1. They tolerate higher temperatures
2. They show a response to high light intensities
3. They have a lower productivity of biomass
4. They lack photorespiration