Mark International needs a typist with a typing speed of 50 WPM. What type of selection test should be conducted?

In the context of hiring a typist, conducting a proficiency, attainment, or competence test is the most suitable choice. This type of test specifically measures the candidate’s ability to perform the typing task at the required speed of 50 words per minute (WPM). It assesses the actual skills that are pertinent to the job, which in this case is typing proficiency.

Proficiency tests are designed to evaluate how well a candidate can execute specific tasks related to their job responsibilities. For a typist, this means assessing their typing speed and accuracy, which directly impacts their effectiveness in the role.

In contrast, other types of tests serve different purposes. An intelligence test measures cognitive abilities and problem-solving skills, which may not directly correlate with typing ability. An aptitude test evaluates a candidate's potential to develop skills or knowledge in the future, but again does not focus specifically on the required task of typing. A general knowledge test examines a candidate's awareness of various subjects, which is not relevant to the typing requirements.

Thus, the most appropriate selection test for Mark International’s need for a typist is one that directly assesses typing speed and competency, making proficiency, attainment, or competence tests the correct choice.