Which option? Help would be appreciated greatly

Answer:
Option 4: 6^7
Step-by-step explanation:
The rule is that when multiplying same bases with different exponents, the exponents only get added.
In other words, (x^a)(x^b)=x^(a+b)
In this case, (6^3)(6^4)=6^(3+4)=6^7
Therefore, Option 4 is correct