Which client instruction is important when the client is scheduled for a vanillylmandelic acid (vma) test? select all that apply 1. avoid caffeine for 72 hours. 2. a 24 hour urine specimen requires starting with an empty bladder. 3. limit physical exercise throughout the test. 4. avoid all commercially prepared foods for 24 hours prior to testing. 5. a preservative will be added to the collection container so no ice is required?