Meaningful girdling (Ringing) experiments cannot be done on sugarcane because

Match Column-$I$ with Column-$II$ and select the correct option.

Column-$I$	Column-$II$
$a.$ Cis-aconitate	$i.$ $4 \ C$-compound
$b.$ $\alpha$-ketoglutarate	$ii.$ $3 \ C$-compound
$c.$ Fumarate	$iii.$ $6 \ C$-compound
$d.$ $1,3$-diphosphoglyceric acid	$iv.$ $5 \ C$-compound

Choose the incorrect statement.

Assertion $A$: Carbohydrates are the primary source of energy in living organisms.
Reason $R$: Glucose is the common substrate used in respiration.
Which option is correct for Assertion $A$ and Reason $R$?

Which of the following processes involves the loss of two protons and two electrons?

How many $ATP$ molecules are produced via substrate-level phosphorylation during the complete oxidation of one glucose molecule in aerobic respiration?