Final answer:
B. Conduct additional diagnostic tests. If adjusting the power and dispensing new lenses doesn't help with unsatisfactory near vision, the next step is to conduct additional diagnostic tests.
Step-by-step explanation:
If a patient has near vision complaints and adjusting with +0.50 at near and dispensing a new distance power is still unsatisfactory, the next step would be to conduct additional diagnostic tests. These tests can help determine the underlying cause of the unsatisfactory near vision and guide further adjustments or recommendations.
Options A and D (recommend a different brand of multifocal lenses and tell the patient to squint) are not appropriate solutions as they do not address the root cause of the issue.
Increasing the near power (Option C) might be a potential solution but should only be considered after conducting additional diagnostic tests to ensure the best possible outcome for the patient.