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The initial drop from a skin puncture can mix with interstitial fluid, skin antiseptic residue, and cellular debris. This admixture dilutes analytes and may affect tests such as glucose, potassium, and hematology parameters. Wiping away the first drop helps ensure that subsequent drops more accurately reflect capillary whole blood composition. Thus, Option C is correct. Option A misattributes anticoagulant to tissue fluid; anticoagulants are in collection devices, not tissue. Option B is not the primary concern—while capillary samples can hemolyze with excessive squeezing, the first drop is wiped primarily due to contamination risk. Option D is incorrect; platelet content is not predictably absent in the first drop. Additional best practices include warming the site to promote flow, using controlled depth lancets (≤2.0 mm for infant heels), avoiding “milking” the site to reduce hemolysis and interstitial dilution, following capillary order of draw (blood gases, EDTA, other additives, serum), and gently inverting microtubes. These steps enhance specimen integrity and are commonly tested in certification exams.