The problem with the traditional view of stegosaurs is that some specimens, like a skeleton of Stegosaurus armatus found nearly a century ago, has metacarpals articulated in a different disposition
A. is that some specimens, like a skeleton of Stegosaurus armatus found nearly a century ago, has metacarpals articulated
B. is some specimens, such as a skeleton of Stegosaurus armatus found nearly a century ago, have metacarpals articulating
C. was that some specimens, such as a skeleton of Stegosaurus armatus found nearly a century ago, had metacarpals articulated
D. had been that some specimens, like a skeleton of Stegosaurus armatus found nearly a century ago, have metacarpals articulated
E. is that some specimens, such as a skeleton of Stegosaurus armatus found nearly a century ago, having metacarpals articulated

OA is C
I understand the past action expressed in option C what about D? An Expert contribution is needed here pls