The phrase "ran riot" is an idiomatic expression often used to describe a situation where individuals or entities act without any checks, boundaries, or limitations. In the given context with the watchdogs asleep, the bulls acting "riot" implies they behaved uncontrollably. After evaluating the options:
1. had the best of time
2. behaved cleverly
3. acted without restraint
4. none of these
the closest meaning to "ran riot" is clearly
acted without restraint. Therefore, the correct answer is option 3.