
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
From 6 students who are good at sprinting, 4 are to be selected to participate in a 4×100m relay race. Among these students, two of them, A and B, must be selected, and B can only receive the baton directly from A. How many different methods of selection are there?

Present the answer in LaTex format: \boxed{Your answer}
user