The official's decision that B1's action of placing both hands on A1 was legal is incorrect. According to standard basketball rules, this should be considered a personal foul.
In the situation described in the question, B1 places both hands on A1 while A1 is dribbling in a game of basketball. The official says this is legal because B1 is allowed one touch. However, the official is not correct. According to standard basketball rules, this would typically be called as a personal foul. A player cannot use their hands to impede the progress of another player who is dribbling. So, the official's decision is incorrect based on standard rules.
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