I guess you can use the post_count parameter for this(post_count=1 in your case since you need just the last entry). You can have a look at the example here –
https://www.livemeshthemes.com/extinct/blog-shortcodes/
[category_posts category_slugs="Nature,Lifestyle" post_count=4 hide_thumbnail="false" show_meta="true" excerpt_count=120 image_size="medium"]