Daguang Machinery Factory has four groups, the first group consists of 9 people, the second group has 10 people, the third group has 11 people, and the fourth group has 12 people. Now the factory department has decided to choose one of the four groups. Inspectors, how many selection methods are there?
大光机械厂有四个小组，第一小组由9人，第二小组由10人，第三小组有11人，第四小组有12人，现在厂部决定在这四个小组中，选一名检验员，共有多少种选法？
<gadget id="calculator">9 + 10 + 11 + 12</gadget>
<output>42</output>

<result>42</result>