Which brand of Central Processing Unit (CPU) is commonly found in laptops?

The Core Duo is a processor that was introduced by Intel and is one of the early dual-core processors designed for laptops. It was well-suited for mobile computing due to its lower power consumption compared to older single-core processors, which helped extend battery life in laptops. This made Core Duo a popular choice for portable devices during its time.

The other options provided represent various Intel CPU families, with different generations and capabilities. Core i7 and Core i5 processors are part of later generations and are typically more powerful, offering enhanced performance for demanding tasks but may be associated with higher power consumption, which is less optimal for battery life. Core 2 Duo was also implemented in laptops, but it is an older generation compared to the Core Duo.

Thus, while the Core Duo is indeed a brand associated with laptops due to its focus on energy efficiency, the other choices are primarily linked to more advanced generations of CPUs that came after it.