Assertion (A): All naturally occurring \(\alpha\)-amino acids except glycine are optically active. Reason (R): Most naturally occurring amino acids have L-configuration.
Assertion (A) is false, but Reason (R) is true.
Step 1: Understanding optical activity of amino acids. All naturally occurring \(\alpha\)-amino acids, except for glycine, are optically active because they contain a chiral carbon atom (except glycine, which has two hydrogen atoms on the chiral center, making it achiral).
Step 2: L-configuration of amino acids. Most naturally occurring amino acids are in the L-configuration, which is why they are optically active (except glycine).
Step 3: Conclusion. Thus, both Assertion (A) and Reason (R) are true, and Reason (R) correctly explains Assertion (A), making option (A) the correct answer.
Which of the following is true for the stereochemical relationship of the given structures (A-D)?

Consider the following molecule (X).
The Structure X is? 
How many different stereoisomers are possible for the given molecule? 

A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?