With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: Chamberlain threw himself into parliamentary work, begrudging the times when he was powerless to attend debates and spending much time on committee work. He was chairman of the national Unhealthy Areas Committee (1919–21) and in that role, had visited the slums of London, Birmingham, Leeds, Liverpool and Cardiff. Consequently, in March 1920, Bonar Law offered him a junior post at the Ministry of Health on behalf of the Prime Minister, but Chamberlain was unwilling to serve under Lloyd George and was offered no further posts during Lloyd George's premiership. When Law resigned as party leader, Austen Chamberlain took his place as head of the Unionists in Parliament. Unionist leaders were willing to fight the 1922 election in coalition with the Lloyd George Liberals, but on 19 October, Unionist MPs held a meeting at which they voted to fight the election as a single party. Lloyd George resigned, as did Austen Chamberlain, and Law was recalled from retirement to lead the Unionists as Prime Minister.
text_B: Was Chamberlain able to serve under Lloyd George?
YES.