This is a difficult question to answer because it is probably in the realms of spherical geometry, not the Euclidean geometry. In the Euclidean sense there is no straight line on the suface of a sphere.
The 0 and 180 degrees longitude can be seen to represent the intersection of the sphere (the earth) with a vertical plane. In that case, any one of the infinite number of lines in that plane will go through both the longitudes - and only those longitudes.
Strictly speaking, the earth is not spherical, and its axis is tilted so the plane would not be vertical, but these details do not affect the argument.
The 120 degrees east line of longitude passes through Asia and Antarctica.
The 60 degrees east line of longitude runs through the Ural Mountains.
Any meridian of longitude between about 53.66 and 73.55 degrees west passes through Argentina. There are an infinite number of possibilities in that range.
110 degrees W through 80 degrees W
Longitude lines measure how far (in degrees) you are East or West of the Prime Meridian (which is a longitude line that runs through Greenwich, England and is designated as 0° longitude).
There are more than one major lines of longitude that pass through the Argentine. They have values around 58 degrees west but none of the lines/meridians is a named line.
The highest longitude lines are the prime meridian at 0 degrees longitude and the 180 degrees longitude line. These lines mark the starting point for longitude measurements to the east and west, respectively.
Longitude lines appear "vertical" and latitude lines appear "horizontal." Every single line of longitude passes through the equator. If you meant to say latitude, then the answer is no. Not a single one (they run parallel).
The answer is equator
It locates a place through degrees
30 deg. north and 20 deg. North
There are 180 degrees of east longitude and 180 degrees of west longitude, for a grand total of 360 degrees of longitude around the Earth. You're free to draw as few or as many 'lines' through that range on your map or globe as you feel will make you comfortable. There is no standard set of 'lines' that everone is required to use.