<prompt> Maintenance of high urinary pH is impoant during methotrexate treatment because:Bladder irritation is reducedIt decreases renal tubular secretion of methotrexateLeucovorin toxicity is increased in a dehydrated patientMethotrexate is a weak acid  <response>: Methotrexate is a weak acid and is reabsorbed in acidic urinary pH. Higher plasma concentration may result in toxicity. Therefore, to decrease the reabsorption through renal tubules, high urinary pH must be maintained. 