Given a paragraph, your job is to generate a question that can be answered from the passage. The answer to your question should be a single entity, person, time, etc. that can be extracted from the passage.

Example input: There are a million times more viruses on the planet than stars in the universe. Viruses also harbor the majority of genetic diversity on Earth. Scientists are finding evidence of viruses as a planetary force, influencing the global climate and geochemical cycles. They have also profoundly shaped the evolution of their hosts. The human genome, for example, contains 100,000 segments of virus DNA.
Example output: How many segments of virus DNA does the human genome contain?
Example explanation: The paragraph states the number of segments of virus DNA does the human genome contain, hence the question asked above is appropriate.
Q: The city is served by the Tyne and Wear Metro, a system of suburban and underground railways covering much of Tyne and Wear. It was opened in five phases between 1980 and 1984, and was Britain's first urban light rail transit system; two extensions were opened in 1991 and 2002. It was developed from a combination of existing and newly built tracks and stations, with deep-level tunnels constructed through Newcastle city centre. A bridge was built across the Tyne, between Newcastle and Gateshead, and opened by Queen Elizabeth II in 1981. The network is operated by DB Regio on behalf of Nexus and carries over 37 million passengers a year, extending as far as Newcastle Airport, Tynemouth, South Shields and South Hylton in Sunderland. In 2004, the company Marconi designed and constructed the mobile radio system to the underground Metro system. The Metro system was the first in the UK to have mobile phone antennae installed in the tunnels.
A:
What underground railways cover much of Tyne and Wear?