Step 1: Observe the tools.
From left to right:
1. Standard pliers – used for gripping, cutting wires, and sometimes nut-cracking.
2. Nutcracker – designed to crack nuts with a pivoting jaw.
3. Scissors (spring type) – used for cutting, has a spring action.
4. Tongs – used for holding, gripping, applying force.
Step 2: Analyze statement (A).
All tools work on the lever principle (pivot point, applying force at handles to exert force at jaws). ⇒ Correct.
Step 3: Analyze statement (B).
Not all can cut fabric. Only scissors are meant for fabric. ⇒ Incorrect.
Step 4: Analyze statement (C).
- The scissors have a spring-back mechanism.
- At least one tool (nutcracker) is for cracking nuts.
⇒ Correct.
Step 5: Analyze statement (D).
Only the nutcracker (2) and possibly pliers (1) can crack nuts, not three of them. ⇒ Incorrect.
Final Answer:
\[
\boxed{\text{A and C}}
\]