Which would do maximum harm to a tree?

Assertion : $C_4$ photosynthetic pathway is more efficient than the $C_3$ pathway.
Reason : Photorespiration is suppressed in $C_4$ plants.

Match the following columns:

Column $I$	Column $II$
$i.$ Mitochondrial matrix	$p.$ Photophosphorylation
$ii.$ Chloroplast stroma	$q.$ Oxidative phosphorylation
$iii.$ Cristae	$r.$ Krebs cycle
$iv.$ Granum	$s.$ Dark reaction

Transpiration and Photosynthesis - a compromise. Give explanation.

How many molecules of water are needed by a green plant to produce one molecule of hexose or to reduce $6$ molecules of $CO_2$?

$I.$ Photosystem-$I$ is a photosynthetic pigment system located on the appressed part of grana and thylakoids.
$II.$ Photosystem-$II$ is a photosynthetic pigment system located on the non-appressed part of stroma only.
Identify whether the given statements are correct or incorrect and choose the correct option accordingly.