Global warming is a phenomenon that is caused by increased greenhouse gas emissions, primarily from human activities such as burning fossil fuels and deforestation. This leads to a rise in global temperatures and has several consequences. The correct answer, option 4, states that global warming is expected to result in all of the listed outcomes.

Option 1: Increase in sea level - This is a direct consequence of global warming as it causes glaciers and ice caps to melt, resulting in a rise in sea levels.

Option 2: Change in crop pattern - Global warming can alter weather patterns, leading to changes in precipitation and temperature. This can impact agricultural practices and the suitability of certain regions for growing specific crops.

Option 3: Change in coastal line - Rising sea levels and increased storm activity due to global warming can result in coastal erosion, leading to changes in the coastal line.

Overall, global warming has wide-ranging effects, impacting not only the environment but also human societies and economies. It is crucial to address this issue and take necessary actions to mitigate its impacts.