Final answer:
Venezuela is the country with Lake Valencia as its second largest lake and the Guri Reservoir. Additionally, the Guiana Highlands in Venezuela are home to the magnificent Angel Falls.
Step-by-step explanation:
The country that has Lake Valencia as its second largest lake and also is home to the Guri Reservoir is Venezuela. Lake Valencia is located in the central part of the country, and the Guri Reservoir, one of the world's largest artificial lakes, is situated on the Caroni River in the Guiana Highlands region. This region also features the stunning Angel Falls, the tallest waterfall in the world. While Lake Maracaibo is often mistaken as the largest lake in South America, it is actually an inlet of the Caribbean Sea. It's important to note that the continent's largest freshwater lake is Lake Titicaca, shared by Peru and Bolivia.