Final answer:
The correct option is A. Excessive lateral tracking of the patella is most likely caused by a shortened iliotibial band and lateral patella retinacular fibers combined with a lax medial collateral ligament, leading to an imbalance in the quadriceps femoris muscle's pull.
Step-by-step explanation:
The factor most likely to contribute to excessive lateral tracking of the patella is A. Shortened iliotibial band and lateral patella retinacular fibers and lax medial collateral ligament.
The lateral forces from a tight iliotibial band and lateral retinacular fibers, combined with a weakness in restraining forces due to laxity in the medial collateral ligament, would lead to an imbalance causing the patella to track laterally. This imbalance in the pull produced by the medial and lateral sides of the quadriceps femoris muscle could result in excessive lateral patella deviation.