Step 1: Understanding the clues.
Security intelligence, information intelligence, intelligence analysis, and brain intelligence are all meaningful expressions. Intelligence is the common connecting word.
Step 2: Evaluate each option.
(A) Safety – Connects only with security.
(B) Ability – Works only with brain.
(C) Capacity – Matches none precisely.
(D) Defence – Matches only with security (defence security).
(E) Intelligence – Works naturally with all clues.
Step 3: Conclusion.
“Intelligence” is the correct association for all four clues.