In each of the questions given below four words are given in bold. These four words may or may not be in their correct position. The sentence is then followed by options with the correct combination of words that should replace each other in order to make the sentence grammatically and contextually correct. Find the correct combination of the words that should interchange. If the sentence is correct as it is then, select option “No interchange required” as your choice.

After having (A) the stress seemed (B) on a president, witnessing (C) access to a personal chef placed (D) to be the best perk of the job.

The correct option is A-C & B-D.

Let's analyze the given sentence and the bolded words to determine their correct placements:

Original sentence: "After having (A) the stress seemed (B) on a president, witnessing (C) access to a personal chef placed (D) to be the best perk of the job."

Step-by-step contextual and grammatical breakdown:

1. Interchanging A and C:
- The phrase "After having the stress..." does not make contextual sense here. Replacing having (A) with witnessing (C) yields "After witnessing the stress...", which is logically and grammatically appropriate.
- Placing having (A) in position (C) yields "...having access to a personal chef...", which correctly completes the noun phrase describing the perk of the job.

2. Interchanging B and D:
- The phrase "...the stress seemed on a president..." is grammatically incorrect. Replacing seemed (B) with placed (D) gives "...the stress placed on a president...", which correctly describes the burden or pressure put upon a president.
- Placing seemed (B) in position (D) gives "...seemed to be the best perk of the job", which correctly links the subject (having access to a personal chef) to its predicate.

Corrected sentence:
"After witnessing (C) the stress placed (D) on a president, having (A) access to a personal chef seemed (B) to be the best perk of the job."

Therefore, the words in pairs (A, C) and (B, D) must be swapped to make the sentence meaningful and grammatically correct.