Final answer:
So the correct answer option is Option D. The KelTec Sub 2000 is a carbine rifle that fires various types of ammunition, including .40-caliber. It is not capable of firing three or four rounds per second, as it is a semi-automatic firearm. The unloaded weight of the KelTec Sub 2000 is approximately six pounds.
Step-by-step explanation:
The KelTec Sub 2000 is a carbine rifle that fires various types of ammunition, including .40-caliber. This means that the statement 'It can properly be called a carbine rifle. It fires .40-caliber ammunition' is true, and not false. Therefore, option (a) is not a false statement about the KelTec Sub 2000.
On the other hand, the statement 'It can fire up to three or four rounds per second' is false. The KelTec Sub 2000 is a semi-automatic firearm, which means it can fire only one round per trigger pull. Therefore, option (d) is a false statement about the KelTec Sub 2000.
Finally, the statement 'Unloaded it weighs about six pounds' is true. The KelTec Sub 2000 is known for its lightweight design, specifically weighing around six pounds when it is not loaded. Therefore, option (c) is not a false statement about the KelTec Sub 2000.