Which one of the following statements is not correct ?

Meridians of longitude are semi-circles that run in a true north-south direction, connecting the North and South Poles [t4][t8]. Unlike parallels of latitude, which are parallel to each other and never meet, meridians are not parallel [t1]. They are spaced farthest apart at the Equator (approximately 111.3 km) and gradually converge as they move toward the poles, eventually meeting at a single point at both the North and South Poles [c2][t2][t3]. Because the Earth is a sphere, an infinite or indefinite number of meridians can be drawn to represent any point on the globe [c4][t3]. Therefore, the statement claiming all meridians are always parallel to one another is incorrect, as their convergence at the poles is a fundamental geometric property of the geographic coordinate system [t1][t7].

Sources

1. [1] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 2: The Earth's Crust > Longitude > p. 11
2. [2] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 2: The Earth's Crust > Great Circle Routes > p. 14
3. [3] https://pubs.usgs.gov/gip/70047422/report.pdf
4. [4] https://oceanservice.noaa.gov/facts/longitude.html