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.

There are some careers (A) where you can’t afford (B) to make even the most disastrous (C) mistake without infinitesimal (D) consequences.

The correct option to interchange is C-D.

Let us analyze the sentence step-by-step to understand the context and grammar:
1. Word A ("careers") fits perfectly in its position: "There are some careers where..." makes logical sense.
2. Word B ("afford") also fits its position well: "...where you can’t afford to make..." is a standard English grammatical structure.
3. Now, let's examine the remaining words C ("disastrous") and D ("infinitesimal"). In the original sentence, it reads: "...to make even the most disastrous mistake without infinitesimal consequences."
- "Infinitesimal" means extremely small or negligible.
- "Disastrous" means causing great damage or ruin.
- Saying that one cannot afford to make a "disastrous" mistake without "negligible" consequences is contextually contradictory, because a disastrous mistake by definition has massive, severe consequences.
4. If we swap C and D, the sentence becomes:
"There are some careers where you can’t afford to make even the most infinitesimal (D) mistake without disastrous (C) consequences."
This version is contextually and logically sound. It correctly indicates that in certain highly sensitive professions, even the smallest (infinitesimal) error can lead to extremely severe (disastrous) outcomes.

Therefore, interchanging C and D makes the sentence grammatically and contextually correct.