Correct option is C
Option (a) is not the best approach as memorizing multiplication tables can be challenging and may not lead to a deep understanding of multiplication concepts.
Option (b) is not advisable as it encourages dependency on calculators and hinders the development of problem-solving skills.
Option (d) can be helpful in demonstrating the multiplication algorithm, but it's crucial for the student to grasp the underlying concepts and apply them independently.
Therefore, option (c) is the most effective approach. By first mastering multiplication of single-digit numbers, the student can grasp the basic principles and then utilize heuristics for two-digit multiplication, which involve patterns and relationships based on their understanding of single-digit multiplication.