A study of college graduates involves three variables: income level, job satisfaction, and one-way commute times to work. List some ways the variables might be confounded. (Select all that apply.)

- One-way commute times may be long because affordable housing is distant from the job.

- A working spouse could affect all three variables.

- People with who are very unsatisfied with their jobs will have a low income.

- People may have a career following their passion, but have a low income or a long commute.

- People with long commutes will have very high incomes.

- People might be very satisfied with their career as long as the income is high.

Please explain your answer. Thank you in advance!