How do I delete photos from my folders in my iPhone 5s?

I am only able to delete some photos. When i select a picture my only options given are to edit (duplicate and edit appears) or to upload. The trash can is not showing my the bottom right corner as it has before. It allowed me to delete some but not others?

When you go into Photos and then Albums, you will see "Select" in the upper right corner. This will allow you to select multiple items to delete.