Which of the following yields the maximum energy $(ATP)$ upon oxidation?

Given below are two statements:
Statement $I$ - $A$ stepwise release of chemical bond energy facilitates the utilization of a relatively higher proportion of that energy in $ATP$ synthesis.
Statement $II$ - Due to stepwise oxidation of respiratory substrate,the same pathway may be used for synthesis of another biomolecule.
In light of above statements,select the correct answer from the options given below.

The intermediate common to both protein and carbohydrate oxidation is:

$A-$ Glycolysis involves only catabolic process.
$R-$ Amphibolic pathway involves both catabolic and anabolic processes.

Describe the metabolic processes of the respiratory pathway.

Maximum energy can be obtained from the oxidation of which respiratory substrate?