A) To complete the table, we need to observe the patterns for the number of shaded, unshaded, and total triangles.

Pattern 1: 2
Pattern 2: 4
Pattern 3: 6
This is an arithmetic progression where the number of shaded triangles is $2 \times \text{Pattern number}$.
For Pattern 4: $2 \times 4 = 8$.

Pattern 1: 0
Pattern 2: 2
Pattern 3: 4
Pattern 4: 6
This is an arithmetic progression where the number of unshaded triangles is $2 \times (\text{Pattern number} - 1)$.

Pattern 1: 2
Pattern 2: 6
Pattern 3: 10
This is an arithmetic progression with a common difference of 4.
For Pattern 4: $10 + 4 = 14$.
Alternatively, Total number of triangles = Number of shaded triangles + Number of unshaded triangles.
For Pattern 4: $8 + 6 = 14$.

The completed table is:

The nth term for the total number of triangles in pattern n is $\boxed{4n - 2}$.