Q: When citing a figure, can I remove the unnecessary part?
If I get permission from a publisher, can I cite a figure from other publication after deleting the unnecessary part for my review paper? For example, if there is Figure 1(A-E), can I use only Figure 1(A)? Or, should I reuse Figure 1(A-E) as a whole, even if Figure 1(B-E) is unnecessary for my paper?
There are several aspects to this question.
First, there is a difference between citing something from an original source and reusing it from there. Citing a figure entails referring to it within the context of an argument in your research paper. However, reusing it entails using the original figure (as is or after recreating it) to support or corroborate your findings. Almost all journals and publishers include information about permissions for the reuse of figures and illustrations in published papers. This information is usually available on the journal’s website and on the article page. Check this information to learn whether you can reuse the original figure and to what extent you can modify the figures.
And you’re right in understanding that you need permission from a publisher. In your case, since you mention that only one part of the figure is relevant to your paper, make sure you mention this in your permission form/email to the journal. Also, often authors choose to recreate original figures in their papers – you could consider recreating the relevant part of the original figure, too. In all cases, you will need to attribute the original source and specify in your journal submission cover letter that you have received the relevant permissions from the journal/author to reuse or recreate the figures.