How many students experienced continuous decrease in marks obtained from 2023…

First, examine the marks for each student in the years 2023, 2024, and 2025.

Student A's marks went from 96 to 92 to 86, which is a continuous decrease.

Student D's marks went from 85 to 81 to 80, which is also a continuous decrease.

Other students did not show a consistent downward trend across all three years (e.g., Student B increased, Student C increased, Student E decreased then increased).

Therefore, exactly two students experienced a continuous decrease.